title: Isolation of seselin from Clausena anisata (Rutaceae) leaves and its effects on the feeding and development of Lucilia cuprina larvae may explain its use in ethnoveterinary medicine.
abstract: BACKGROUND
  The leaves of Clausena anisata are used traditionally to expel maggots from wounds of animals in Zimbabwe. We have previously proved in the laboratory that the plant certainly affects the behaviour and growth of blowfly larvae. The objective of this study was to isolate and identify the active compounds responsible for this activity.
  
  
  METHODS
  The acetone extract of Clausena anisata leaf powder was separated by solvent-solvent partition into five fractions. The n-hexane fraction was the most active in the larvicidal assay and therefore subjected to open column chromatography on silica gel.
  
  
  RESULTS
  The isolated compound was identified by nuclear magnetic resonance (NMR) and mass spectroscopy (MS) as the pyranocoumarin, seselin, chemically known as 2',2'-dimethylpyranocoumarin. It inhibited feed intake in the first and second instars of blowfly larvae at the minimum concentration tested of 1 ppm resulting in significant lower mass pupae (13.5±0.5 mg and 22.4±0.4 mg for the first and second instar larvae respectively) compared to the solvent control group (26.19±0.8 mg) (p<0.05).
  
  
  CONCLUSIONS
  This is the first report of the isolation of seselin from the leaves of Clausena anisata and the first report of the compound having an effect against blowfly larvae.
authors.affiliation: Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, P. Bag X04, Onderstepoort 0110, South Africa. Electronic address: lmukandiwa@yahoo.com.
authors.forename: L
authors.initials: L
authors.lastname: Mukandiwa
authors.forename: A
authors.initials: A
authors.lastname: Ahmed
authors.forename: J N
authors.initials: JN
authors.lastname: Eloff
authors.forename: V
authors.initials: V
authors.lastname: Naidoo
mesh_terms: D000818:Animals; D003374:Coumarins / Q000302:isolation & purification / Q000494:pharmacology*; D004175:Diptera / Q000187:drug effects* / Q000502:physiology; D004435:Eating / Q000187:drug effects; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects / Q000502:physiology; D009198:Myiasis / Q000188:drug therapy / Q000662:veterinary; D018515:Plant Leaves / Q000737:chemistry; D027821:Rutaceae; D014730:Veterinary Medicine
chemical_list: D003374:Coumarins; D007306:Insecticides; C516746:seselin
keywords: Blowfly development; Clausena anisata; Seselin